Aluminum and calcium sulfate incendiaries have been used for specialized purposes for a number of years. However, this mixture has never been used to a great extent for several reasons, each one being sufficient to prevent its general use. They are:
1. To obtain sufficient heat on a unit weight basis the amount of aluminum has to be increased to the point that ignition becomes too difficult. PA1 2. During the curing exotherm some of the aluminum is attacked by the calcium sulfate water mixture used, with the evolution of hydrogen gas. PA1 3. When the cast mixture is heated for an extended period of time at temperatures of 150.degree. F. and higher, gas is evolved which in itself makes the material unsuitable for use in normal magazine conditions. In addition at least part of this gas is water of hydration from CaSo.sub.4.2H.sub.2 O, the loss of which causes the physical properties of the cast material to deteriorate. PA1 4. The cast material is too light. Therefore its volumetric loading efficiency is not adequate.